Floating roof anti-rotational mechanisms



Nov. 24, .1964 J. H. WlGGlNS FLOATING ROOF ANTI-ROTATIONAL MECHANISMS 5 Sheets-Sheet 1 Filed NOV. 1, 1962 F/GJ INVENTOR.

JOHN H. W/GG/NS Qua; P

g wrrrs.

GBY

Nov. 24, 1964 J. H. WIGGINS FLOATING ROOF ANTI-ROTATIONAL MECHANISMS 5 Sheets-Sheet 2 Filed Nov. 1, 1962 INVENTOR Nov. 24, 1964 J. H. WIGGINS FLOATING ROOF ANTIROTATIONAL MECHANISMS Filed Nov. 1, 1962 5 Sheets-Sheet 3 INVENTOR JOHN H. W/GG/NS Nov. 24, 1964 FLOATING ROOF ANTI-ROTATIONAL MECHANISMS Filed Nov. 1, 1962 FIG.

J. H. WIGGINS 0 5 Sheets-Sheet 5 INVENTOR; JOHN H. W/GGINS ATTYS.

United States Patent FLOATING ROOF A v II-ROTATIONAL MECHANISMS John H. Wiggins, 801 C 'El Camino Real, Menlo Park, Calif. Filed Nov. 1, :1962,-Ser. No. 23 L805 20 Claims. (ill. 220-26) The present invention relates t o storage tanks .for liquids, particularly petroleum .products, .or the like and pro- .vided with floating roofs, ,and .more particularly :to antirotational mechanisms .fortthe floatingroofsin the storage tanks.

.A storage :tank :of the type mentioned conventionally comprises .an upstanding substantially cylindrical side wall provided with an open top; and a substantiallydisk-shaped piston-like floating roof is arranged .in the tank in floating relation with the stored liquid and movable .in the vertical direction with respect :to the side .wall in accordance with the head of the stored liquid. The floating roof is positioned radiallyinwardly withrrespectto the side wall to provide a substantially annular space therebetween; and substantially annular sealing structure iscarrfied .bytheperiphery of the floating roofand .arranged in the annular space and disposed in slidingisealed engagement with the side wall. Thus, the floating roof is subjectto rotation in a generally horizontal plane with-respect to thezside wall, particularly when .the floating :roof is subjected to-a wind or rain storm; and ofcourse suchrotation oithe floating roof .through any substantially angle -.with respect to its normal position in the tank is highly objectionableandmay cause substantial damageto various appliances andfixtures carried by the floating roof.

While a number of mechanisms have been proposed ,heretoforeto prevent or-to limitsuch rotationof the floating roof with respect to the tank, .nonetof these mechanisms has been entirely satisfactory in operation and all of these mechanisms have been altogether too expensive.

Accordingly, it ,isa general object-ofthe present-invention to provide an anti-rotational mechanism for a {floating roof (that is both entirely satisfactory -in operation and economical to rnanufactureandto maintainin service.

Another object of the invention :is to provide .a mechanism for controlling and limiting the rotation ofta floating roof with respect to its normal rotary centered position within the side wall of the associated storage tank .-that essentially comprises a strong flexible .resilient-, cable arranged in the tank and secured in tauttcondition between upper and lower anchor structures rigidly secured to the side wall of the tank \respectivelyadjacent to the topiand to the bottom thereof, wherein the .cable .is :normally disposed in a Substantially vertical position extending through a cooperating upstanding opening :provided in the peripheral portion of the floatingroof when the floating roof occupies its normal vrotary :centered position, whereby undesirable rotation of the floating roofiin either direction out of its normal rotary centered position efiects corresponding deflection of theintermediatesection of the cable passing through the upstanding opening mentioned from its substantially vertical position, so that the thus deflected cable exerts a force upon the floating roof that is productive of a torque thereupon tending to restore the floating -roof back into its normal rotary centered posi- .tion.

Another object ofthe invention is to provide a mechanism of the character described that also comprises a cable guiding device carried by the floatingroof adjacent to .the upstanding opening therein and cooperating with the adjacent intermediate section ofthe cable.

Another object-of the invention is to provide a mechanism of the character described, wherein the-incorporated cable guiding device is operative to resolve an undesirable 3,158,280 Fiatented Nov. 24,, 19.64

rotary movement of the floating roof in either direction out ofdts normal rotary centered position intdcorresponding circumferential and radial components.

A furthertohject of the invention is to providea mechanisrn of [the character-described that further comprises .a seal arranged .to (Prevent the escape of vapors from the stored liquid through the npstandingopening in :the floating roof. a

A further object of the invention ito provide a mechanism -of ithe character described ,that further comprises :a seal arranged .to prevent the entryof train and the other elements of weather into the incorporated cable guiding device.

Further features of ,the invention pertain .to .the partieular arrangementof the elements of ,the anti-rotational mechanism (for .the zfloating roof, whereby the above-outlined and additional operating features thereof are .attained.

The invention, both .as to itsorganization ,and vmethod of operation, together with further tobjects and-advantages h r f, will he understood by reference to 1116 following specification, taken in connection with the ac ompanying drawings, in which:

FIGURE ,1 ,is a stop perspective view, partly broken away, of ,a tank ,for storing liquids, such as petroleum roducts, and provided with a floating roof and incorporating an anti-rotational mechanism for the floating roof embodying the present invention;

FIG. 2 is an enlarged top perspective view of fragmentary ,portions of the storage tank, the floating roof and a sealing mechanism carried'by the floating roofand arranged in slidingisealed engagement .with the side Wall of the storage tank;

FIG. 3 is an enlarged top perspective View, partly broken away, of the anti-rotational mechanism;

iFIG. '4'is a further enlarged vertical sectional view of a tensioning device incorporatedin the antifrotational mech anism, as shown in FIG, 3;

FIG. 5 is afurther enlarged horizontal sectional view of the "tensioning device, this view being taken in the direction of thearrows along theline 5'5 ,inFIG. 4;

FIG. dis a-further enlarged horizontal sectional view of the tensioning device, this view being' takenin the direction of the arrows along the 'line 6-6 in FIG. '4;

*FIG. 7 is a diagrammatic view of the mode of resolvingforces exerted upon the floating roof into corresponding radial and circumferential components;

FIG. 8 is a further enlarged plan view, partly broken away, of-a-modified form of acable guiding device that may be incorporated in the anti-rotational mechanism, as shown-'in FIG. 3; 7

FIG. 9 is a further enlarged vertical sectional rview of-the'cable guiding device, this view being taken in the direction of the arrows along the radially extending line 9-9 in FIG. :8;

FIG. 1-0 is a further enlarged vertical sectional .view of the'cable guiding device, this view-being taken in the direction of the arrows along the circum'ferentially extending line IO-10 =in1FIG. 193

FIG. 1 1 is afurther enlarged plan view, partly broken away, ofanother modified form of a cable guid ing device that may be incorporated in the anti-rotational mechanism, as shown inFIG. 3; and,

FIG. 12 is a further enlarged vertical sectional ,view of the cable guiding device, this View being taken inthe direction of the arrows along the radially extending line- Referringnow-to'FIGS. 1 to 3, inclusive, of the draw- 3 open top. The top of the side wall 11 terminates in an annular radially outwardly directed curb 13; and an annular radially outwardly directed wind girder 14 is carn'ed by the upper portion of the side wall 11 and arranged below'the curb 13. The wind girder 14 projects radially outwardly well beyond the curb 13 and is supported by a plurality of circumferentially spaced-apart gusset plates 15 arranged between the bottom of the wind girder 14 and the adjacent upper portion of the side wall 11. The outer periphery of the wind girder 14 terminates in a formed rim 16 that extends first upwardly and then radially inwardly and ultimately downwardly.

Arranged within the storage tank 10 is a floating roof 20 that essentially comprises a substantially disk-shaped hollow central pontoon 21, a substantially annular hollow outer pontoon 22, and a substantially annular deck sheet 23 joining the pontoons 21 and 22. More particularly, the outer pontoon 22 comprises an outer rim 24, an inner rim 25, a top plate 26 joining the top portions of the I rims 24 and 25, and a bottom plate 27 joining the bottom portions of the rims 24 and 25. The outer rim 24 of the outer pontoon 22 is substantially cylindrical and is disposed in upstanding position and spaced radially inwardly with respect to the side wall 11 of the storage tank 10, so as to provide an annular space 28 therebetween.

An annular sealing mechanism 30 is carried by the outer rim 24 of the outerpontoon 22 and arranged in the annular space 28 and disposed in sliding sealed engagement with the side wall 11 of the storage tank 10. The sealing mechanism 30 may be of any suitable type, such, for example, as that disclosed in US. Patent No. 3,043,468, granted on July 10, 1962, to Frank W. Horner, Ir.

An annular weather hood is carried by the top of outer rim 24 of the outer pontoon 22 and is directed upwardly and radially outwardly over the top of the annular space 28 and positioned above the sealing mechanism 30 and cooperates in sliding engagement with the side wall 11 of the storage tank It). The weather hood may be of any suitable type, such, for example, as that disclosed in US. Patent No. 2,997,200, granted on August 22, 1961, to Anthony P. Giannini and Eli F. Smith.

Further, the storage tank 10 comprises an anti-rotational mechanism 50 for the floating roof 20; which mechanism 58 embodies the features of the present invention. More particularly, as shown in FIGS. 1 and '3, the anti-rotational mechanism 50 compn'ses upper anchor structure 60 arranged at the top of the tank 10, and lower anchor 70 arranged in the tank 10 adjacent to and above the bottom Wall 12'thereof. The upper anchor structure 60 includes a substantially horizontally disposed beam 61,

the intermediate portion of which is rigidly secured to the top of a short upstanding column 62. The bottom of the column 62 is rigidly secured to a plate 63, that is, in turn, rigidly secured to the curb 13. The outer end of the beam 61 projects radially outwardly over the wind girder 14; and the extreme outer end of the beam 61 is rigidly secured to the wind girder 14 by a tie bar 64 extending-therebetween. Specifically, the upper end of the tie bar 64 is rigidly secured to the extreme outer end of the beam 61 and the lower end of the tie bar 64 is rigidly secured to the rim 16 of the wind girder 14. The inner end of the beam 61 projects generally radially inwardly into overhanging relation with the outer peripheral portion of the outer pontoon 22. The lower anchor structure 71 includes a substantially horizontally disposed beam 71; the outer end of the beam 71 is rig-idly secured to the side wall 11; and the outer end of the beam 71 projects generally radially inwardly into underhanging relation with the outer peripheral portion of the outer pontoon 22. Also the outer end portion and the intermediate portion of the beam 71 are rigidly braced to the side wall 11 against undesirable upward bending relative to the side wall 11 by a number of SttUCfiiIal elements 72, 73 and 74. Specifically, the plate 72 is rigidly secured mutually to the outer end of the beam 71 and to the adjacent portion of the side wall 11; the angle 74 is rigidly secured to the side Wall 11 at a position disposed above the plate 72; and the strut 73 is disposed in an upwardly and radially outwardly directed position between the intermediate portion of the beam 71 and the angle 74, the lower end of the strut 73 being rigidly secured to the intermediate portion of the beam 71 and the upper end of the strut 73 being rigidly secured mutually to the side wall 11 and to the angle 74.

In the mechanism 50, the upper and lower beams 61 and 71 are disposed in vertical alignment with each other;

' the extreme inner end of the upper beam 61 carries a tensioning device 80 rigidly secured thereto; the outer end of the lower beam 71 carries an upwardly directed lug 75 rigidly secured thereto; and the tensioning device 30 and the lug 75 are disposed in vertical alignment with each other for a purpose more fully explained hereinafter.

Referring now to FIGS. 4, 5 and 6, the tensioning device 84! essentially comprises an upstanding substantially cylindrical casing 81 including a tubular side wall 82, a bottom wall 83 rigidly secured in the bottom end of the i side wall 82, and a top wall 84 removably secured in the top of the side wall 82, the upper portion of the side wall 82being rigidly secured to the extreme outer end of the upper beam 61. An upper piston 85 is mounted in the upper portion of the side wall 32 for vertical adjusting movements, the central portion of the piston 85 carrying an upwardly directed rod 86 rigidly secured thereto. Two radially outwardly directed and diametrically disposed lugs 87 are carried by the piston 85 and arranged in two upstanding parallel guide slots 82a formed in the inner wall of the side wall 82, thereby to prevent rotation of the piston 85 with respect to the side wall 82, The upper end of the rod 36 is threaded, as indicated at 86a, and projects to the exten'or of the casing 81 through a centrally disposed hole provided in the top wall 84; which 3 threaded upper end of the rod 86 carries an adjusting nut 88 and a lock nut 89 both disposed above the top wall 84.

A lower piston 90 is mounted in the lower portion of the side wall 82 for vertical adjusting movements; and the two pistons 85 and 90 are rigidly connected together by a pair of oppositely disposed vertically extending straps 91. Thus, the vertical position of the piston 85 may be selectively adjusted by appropriate adjustment of the nut 88 on the rod 86; and this adjustment may be preserved by setting the lock nut 89. Asthe vertical position of the piston 85 is adjusted, the vertical position of the piston 99 is likewise adjusted through the straps 91 rigidly connected between the pistons 85 and 90. An intermediate piston 92 is mounted in the intermediate portion of the side wall 82 for vertical movements independently of the i pistons 85 and 90; and a pair of oppositely disposed notches 92a are formed in the sides of the piston 92 to receive the straps 91, so as to prevent rotation of the piston 92 relative to the side wall 82. An upstanding rod93 passes through aligned holes respectively provided in the central portions of the bottom wall 83 and the two pistons 99 and 92; and the extreme upper end of the rod 93 carries an enlarged head 94 engaging the top surface of the piston 92. A resilient helical compression spring 95 is arranged in surrounding relation with the upper portion of the rod 93 and interposed with respect to the pistons and 92.

In the tensioning device 80, when the rod 93 is moved downwardly, the piston 92 moves downwardly therewith, whereby the spring is compressed between the pistons 92 and 90, thus resiliently opposing the downward movement of the rod 93. ,Also, the compression of the spring spring '95, may be selectively adjusted by manipulation of the nuts 88 'and 8,9, as previouslytexplained.

Again referring to RIG. 3, an upstanding tube 96 is :arranged between the upper and lowersheets 26 and .27 :in the outer peripheral portion of the outer .pontoon 22, the upper and l'lowerendsof :the tube96being suitably hermetdcally sealed in :place in corresponding openings respec- =tive1y rovided :in the sheets 26sand27. The floating roof 120 has a normal rotary 'centered'position-with respect to the side wall 111 of .the storage'tank 10, as explained more iullyhereina'fter, wherein :the upstanding-passage provided through the tube 916 istarranged :in vertical alignment with respect to the tension device 380 carried on the inner 'end of the upper beam ;61 and\the lug 75 carricd onzthe inner end: of .the .lower beam 1.

Further, the mechanism 50 comprises a strong flexible mesilient cable 97 .operatively connected between the .lug .75 andithe tension -:device 80 and extending zthrough'the ulpstanding passage :provided'in :the tube=96; whichicable 9.7 :is preferably :of 'Ihe ctwisted strand type and formed :essentially of stainless steel, thereby to obtain .the .quality of corrosion resistance, ritogether with strength, .flexibility and :resiliency, as noted (above. :Specifically, :the lower send of (the rod 93 carried :by the tension device 80 termimates :in a clevis "98 :rotatably secured :thereto; and :the upper end of the cable 97 is looped through the.clevis 98 land flrmlyrseuured upon itself :by cable :clamps =99; and the lower end of ithfi cable :97 is looped "through :a hole :provided in xthe Elug 75 ;and firmly secured upon itself :by cable clamps 100. ?In the :arrangement the cable 97 is maintained in :taut condition between :the clevis 298 and tthe lug 75 by the tension devicefitksand the tin'itialtt'ension -in*thecablet'97 is preset, as desired, by .adjustmentofathe .nuts :88 and :89 with respect to "the rod 7&6, ;in the :manner previeuslytexplained. When the :floating roof ,2flioccupies its normal rotary centered position :with respectito the side wall 1110f the tank 10, the cable 97 :is disposed inia sub- ;stantially verticalpositionpassingthrough the tubea96rand tout of contact therewith-by virtue :of the :previously :mentioned vertical alignment of the upstanding opening in the tube 96 with the clevis- 98 and the ;lug 7.5 and :the initial tensionin the cable 97 -isestablished and :rnaintainedby ;the tension-device 80. In passing Sit is mentioned thatzto .the inherent resiliency of Ihecable 971, :the :resiliencyiof .-the compression :spring :95 incorporated in ;the tension -..device 189 is added, in the overall mounting arrangement of the .cable 97 between the clevis %98 and :the .:lug 7.5.

Further, -.the .mechanism 50 comprises a cable guiding device lltl-carried iby rthe outer pontoon .22:ofzthe:floating roof and cooperating with the intermediate tsectiontof .theicablet97just above-.the-top of=the=tuhe 9,6. :Specifically, the .cable guiding device 110 comprises;a:pair ofzupstandv.ing plates 11-1 rigidly secured :to .the top surface of :the top plate 26 of the outer pontoon 22;Whi0hxPlfit6S 1'11 extend in the circumferential direction of :the floating roof 20 :and are spaced-apart in the radial direction of the floating roof 26. A pair-of elongated spindles 11-2 vare carried -by*the plates .111; which spindles 112 extend radially and vare disposed incircumferential spaced-apart relation with respect to the floating roof .20, the spindles v112 .being respectively arranged on opposite sides of the adjacent intermediate section of the cable 97. A pair of elongated rollers 113 are respectively rotatably mounted pupon'the-spindles 112'andtrespectivelycngage:the opposite sidesof the adjacentintermediatesection of :thetcable 97. 'Thus, the cable97 passest throughrthe cable guidingdevice 110,'and thence through'the tube 96, the cableibeing boxed or framed by theipair-ofrplates 111 andihe pair of rollers 1-13. Thus, it willibe understoodthat 'asthe floating roof 20 rises and falls in accordance with the head of the stored liquid and with respect to the side wall 11' of the tack 10, the cable 97 is -fed through the cable guiding device 1145 in'the required direction, and without the-exertion of any particular force between the cable 97 and the cable guiding device 110, as long as the floating roof 2d occupies its normal rotary centered position with respect to the side wall 11.

Referring now to FIG. 7, there is diagrammatically shown the floating roof 20, the sealing mechanism 30 carriedv by the outer rim 24- of the outer pontoon 22 thereof, :the-side wall :11 of the storage-tank 1 0, the cable 97 and the cable guiding device wherein 'the floating roof '20 occupies its normal rotary centered position with respect to the side wall 11, with the result that the sealing mechanism 30 is substantially uniformly compressed .radially about the circumference thereof between the floating roo'f 20 and the side wall 11. Now, the wind may exert a force-upon the ficating roof it) from any direction whatsoever, tending to move the same from its normal centered position, tending to rotate the same about it own center, etc. For purposes of explanation, it is convenient to consider the major horizontal axis of the floating roof 20 as being oriented W-E and passingthrough the cable 97 in its vertical position. A force SW exerted upon the floating roof 20 may be resolved into a horizontalcom-ponent W1 and a vertical component S1; a force NW exerted .upon the floating roof 20 may be resolved int-0 a horizontal component -W2 and a vertical component N2; a 'NE'force-exerted upon the floating roof 20 maybe resolved into a horizontal component E3 "and a'verti'cal component N3; and waSE force exerted upon the floating roof 20 may be "resolved into -a horizontal --component E4 and .a vertical component 84. The componentsiEBand :E4:tend-;to shift the roof 20 horizontally toward the East with respect to the cable 97 and with respect to the East side wall 1-1, thereby corresponding further to compress the :East seg- 'mentof the resilient sealing mechanism 30; and the corn- =ponents W1 and W-2 tend-to=shift the-roof horizontally toward the -West with respect to the cable 97 and :with respect ;to the West side =w-all 11, thereby correspondingly further to compress the West segment of the resilient sealing mechanism 30. The components '81 and S4 tend to rotate the roof '20 in *the counterclockwise direction about the cable 97 and further .to compress the Southsegrnent of the resilient-sealing mechanism 30;.and the components N2 and N3 tend to rotate the roof 20 in the clockwise direction about the cable and further to compress the North segment cf the resilient sealing mechanism '30. Shi'fiting of the roo f'-20 either East-or West with respect to thecab-le 97 eflects no particular force thereupon, since the rollers "113 incorporated -in the cable guiding device '1-1'0 accommodate ready "and unrestrained relative radial movements of -the cable 97withtrespect-thereto. :However, rotation of the roof -in either direction "about the cable 97 effect corresponding forces u-pon the-cable 97, since the rollers T13 "incorporated in the cable guiding device 1 10 resist relative circumferential movements of the cable 97 with respect thereto, whereby the intenmediate section of the cable i -corresponding'lydeflected from its verticalposition. Further, it is pointed out'that atrue spinning rotation of the roof 20 in either-direction about its own center also produces a corresponding SofiN-force applied hetween the rent '20 and the cable 97 by the cable guiding device 110, whereby the intermediate section of "the cable iscorresponding'ly deflectedfrom itsverticeil "position. .Anyfurther-compression of any segment of the resilient sealing mechanism d0 iis productive of a conespondingoppos'ing and restoring force upon thereof 20; and ianydeflection df=the intermediate section o'f the cable 97 out of its normal vertical position or attitude is productive of a corresponding opposing and restoring force upon the roof 20. Thus, both the sealing mechanism 30 and the cable97 tendto-restore-the floatingroo'f ZOYback into its \normal centered position with respect to the side wall dl in the'eyent of movement therefrom of the roof 20. In the arrangement, the cable 97 is -very effective in restore the floating roof"20 backiinto its normal rotary centered position in the -event of.a true spinning rotation "thereof a'bout i ts own center.

Reverting to ":FIG. "3, it is mentioned the tube 96 is substantially rectangular in horizontal cross section, including two relative long sides 96a extending in the radial direction and two relatively short sides 96b extending in the' circumferential direction;v whereby the upstanding opening extending through the tube 96 is Wide or long in the radial direction and narrow or short in the circumferential direction; which arrangement accommodates relative radial movement of the cable 97 between the rollers 113 and prevents any substantial circumferential movement of the cable 97 between the rollers 113; whereby there is no drag or interference between the cable 97 and the tube 96 in the relative movements of the cable 97 with respect to the tube 96 and through the tube 96. Thus, the coaction between the cable 97 and the cable guiding device 119 not only opposes and limits movements of the floating roof 20 out of its normal rotary centered position, but also restores the floating roof 20 back into its normal rotary centered position following a movement therefrom, as explained above. Of course, the character of the above mentioned coaction may be preset by proper adjustment of the initial tension in the cable 97, when it occupies its normal vertical position; which adjustment may be readily accomplished by adjustment of the tension device 89, in the manner previously explained.

In connection with the operation of the mechanism 59, it is noted that the forces produced in the cable 97 are transferred by the beams 61 and 71 directly to the side wall 11, and independently of the bottom wall 12; which arrangement is very advantageous, since the side wall 11 is initially stiff and is further stiffened by the stored liquid in the tank 10. The exclusion of the bottom wall 12 from this connection prevents working of the bottom wall 12, the usual oil-can effect thereof, whereby the characteristics of the mechanism 50 may be accurately preset and maintained in the operation thereof over the total band of variable conditions encountered thereby and relating to weather, to the head of the stored liquid in the tank 10, etc. Further, it is noted in this regard, that any desired additional stiffness may be readily introduced into the side wall 11 by the simple expedient of rigidly securing to the exterior surface thereof one or more upstanding beams or columns, not shown, arranged in the vicinity of the mechanism 50. For example, a rigid column might extend from the curb 13 to the bottom wall 12 through an opening provided in the wind girder 14, such column being positioned substantially below the column 62 and arranged in upstanding position in contact wtih the exterior surface of the side 11 and suitably rigidly secured thereto. 7

Referring now to FIGS. 8 to 10, inclusive, a modified form of the cable guiding device 120 is there illustrated, which is considered at the present, to comprise the preferred and most advantageous fonm thereof. In this embodiment, the top end of the tube 96 projects upwardly somewhat above the top plate 26 of the outer pontoon 22, as indicated in FIGS. 9 and and the device 120 comprises a pair of upstanding radially extending plates 121 arranged in circumferentially spacedapart relation and respectively rigidly secured at the bottom ends thereof to the top ends of the long sides 96a of the'tube 96, and a pair of upstanding circumferentiallyextending plates 122 arranged in radially spacedapant relation and respectively rigidly secured at the bottom ends thereof to the top ends of the short sides 96b of the tube 96. The plates 121 project only somewhat above the top end of the tube 96 and terminate in oppositely directed flanges 123 disposed in a lower substantially horizontal plane; while the plates 122 project well above the top end of the tube 96 and terminate in oppositely directed flanges 124 disposed in'an upper substantially horizontal plane. A pair of elongated spindles 125 are carried by the plates 122 in an intermediate substantially horizontal plane, the spindles 125 extending in the radial direction and being spaced-apart in the circumferential direction. As a practical matter the spindles are parallel to each other, since the radial distance between the center of the floating roof '20 and the spindles 125 is so great relative to the lengths of the spindles 125; and further the spindles 125 are arranged on opposite sides of the long sides 96a of the tube 96, as best shown in FIG. 10. The spindles 125 may be firmly secured in place upon the plates by nuts 126 carried upon threaded outer ends thereof, as best shown in FIG. .9. Two rollers 127 and 128 are respectively mounted upon the spindles 125 for both rotation thereabout and slidingmovements therealong, the two rollers 127 and 128 being respectively carried by two elongated bearing sleeves 129 and 130 to improve the stability thereof. The roller 128 is in the .form of a sheave pulley and comprises a central cylindrical barrel 128a and a pair of enlarged side flanges 12812; which side flanges 128b respectively embrace the sides of the roller 127', whereby the two rollers 127 and 128 are locked together for movements along the respective spindles 125. The cable 97 is arranged between the rollers 127 and 128; the outer periphery of the roller-127 and the outer periphery of the barrel 128a of the roller 128 respectively engage the opposite sides of the cable 97; and the flanges 128k trap the cable 97 in place therebetween. a

In view of the foregoing, it will be understood that vertical movement of the cable 97 in either direction through the tube 96 merely effects rotation of the rollers 127 and 128 upon the spindles 125; and radial movement of the cable 97 in either direction effects corresponding sliding movements of the two rollers 127 and 128 along the respective spindles 125. On the other hand, the two rollers-127 and 128 respectively oppose circumferential movements in the respective directions with respect to the tube 96 of the cable 97, whereby the corresponding one of the rollers 127 and 128 efiects deflection of the intermediate section of the cable 97 from its normal vertical position for the purpose previously explained.

The cable guiding device 120 incorporates a lower sealing device for the purpose of minimizing the escape through the tube 96 of vapors from the liquid stored in the tank 10; which device 140 essentially comprises a sheet 141 formed of rubberized fabric, or the like, and arranged on top of the flanges 123 carried by the tops of the plates 121; which sheet 141 is suitably clamped in place by a pair of ovenlying strips 142 respectively secured to the flanges 123 by rivets 143. The

sheet 141 has an elongated slit 141a therein through which the'cable 97 passes; whereby the sheet 141 closely surrounds the cable 97, while the slit 141d therein accommodates the required radial movements of the cable 9'7 with respect to the tube 96.

The plates 12 carry a hood 145 that includes a top wall 146 and a pair of downwardly directed side walls 147, the top Wall 146 being disposed above the rollers 127 and 128' and rigidly secured to the flanges 124 carried by the plates 1 22; which top wall 146 has an elongated radially extending slot 146a therein, so as to accommodate the required radial movements of the cable 97 with respect to the tube 96, without interference by the top wall 146 of the hood 145. The hood 145 incorporates an upper sealing device 156 for the purpose of minimizing the entry of rain and the other elements of weather into the hood 145 and thence into the rollers 127 and 128 and onto the spindles 125; which device 150 essentially comprises a sheet 151 formed of rubberized fabric, or the like, and arranged on top of the top wall 146 of the hood 145 and in covering relation with the slot 146a formed in the top wall 146; which sheet 151 is suitably clamped in place by a pair of overlying strips 152 respectively secured to the top wall of the hood 145 and to the flanges 124 by rivets 153. The sheet 151 I has an elongated slit 151a. therein through which the {9 "cable "97 passes; whereby the sheet 151 closely surrounds the cable 97, while the slit 151a therein accommodates the required radial movements of the cable '97 with respect to the tube 96.

The hood 14-5 and the sealing-device 150 cooperate to protect the rollers 127 and 128 and the spindles 125 against rain and the other elements of weather; which arrangement is very advantageous, since a freezing rain and the resulting ice could easily lock the rollers 127 and 128 to the respective spindles 1-25, thereby preventing both rotation and sliding of the rollers 127 and 128 upon the "spindles 125, so as greatly to interfere with the normal and desired mode of operation of the cable guiding device 129, in the manner previously explained.

Referring now to FIGS. 11 and 12, another modified form of the cable guiding device 160 'is there illustrated; and in this embodiment, the top end of the tube '96 projects upwardly somewhat above the top plate 26 of the outer pontoon 2'2; and rigidly secured to the top of the tube 96 is a cover plate 96x having an elongated radially extending slot 96y therein. The device Mil-comprises 'apairof radially-extending and circumferentially spacedapart upstanding 'rails 161 rigidly secured to the top of the cover plate 96x, the rails 161 being substantially parallel to each other, since the radial-distance from the center of the 'floatingroof 20 to the rails 161 is so great relative to the dimensions of the rails 161. "The rails 161 carr-y at the tops thereof a pair of inwardly directed flanges 162 disposed in substantially parallel spaced-apart relation and extending in the radial direction. An annular race 163 is arranged between the adjacent edges of the flanges 1'62; which race 163 carries at the top and bottom ends thereof two annular washers 164 and 1 65 that are rigidly secured thereto. The top and bottom washers 1'64 and 155 are respectively positioned above and below the'fianges 162; whereby the race 163 is mount ed for radial sliding movements between the flanges 1'62. Aligned holes are centrally-disposed in the washers 164 and 165; the cable 9-7 extends vertically through the slot 96y provided in the cover plate 95x, and through the race =163, and also through the holes provided in the washers 164 and 165. Finally, the device 160 comprises a plurality of balls 1&6 formed of bronze, or the like, and arranged iinteri'or'ly of the race 163 and exteliorly of the adjacent section of thecable 97 and in engagement with the -cable*97 'and the race 163; and thespaces between the balls 1'65 and "between the balls 166 "and'the race 163 maybe filled with a suitable heavy grease, not shown, to insure easy rollingiof the balls 156.

.In view of the foregoing, it will -be understood that vertical movement of the cable 97 in either direction through the tube L96 merely efiects rolling of the balls "166m the race 1'63; and radial movement of the cable in either direction sitcom-corresponding sliding enrolling movements, as required, of the unit including the 'race 163, the balls 166 and the washers Mind 165 along the iflanges 162-. On the other hand, the balls 166 1)- pose circumferential movements in the respective directions withrespect to the tube'96 of the cable=97, whereby the balls l dii-efiiect deflectionof the intermediate section of the cable 97 from its 'normal vertical'positiontor-the purpose previously explained.

In the cable guiding devices 1 16 and 160 no lower and upper sealing devices, respectively corresponding to the sealing structure 140 and 150 incorporated in the-cable guiding device 1-20, have been disclosed as being "incorpora-ted therein; however, it will be understood that such sealing structures could be readilyincorporated into the cable guiding devices 110 and 160 in a-manner following the disclosure made in conjunction with the cable guiding device 120.

In view of the foregoing it is appmentthat there'has beenprovidedan anti-rotationahmechanism for a floating roof arranged in a storage tank for iliquids, such .as .petroleum products, wherein the mechanism is of improved and :economical construction and arrangement-and is positive and simple in operation.

While there has beenvdescribed What is at present considered to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein, and it is intended 1110 cover in the appended claims all such modifications .as fall "within the true spirit and scopeof the invention.

What is claimed is:

1. In a tank for storing liquids, such :as petroleum products, including an upstanding substantially cylindrical side wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the :head :of the stored liquid, said floating roof being positioned radially inwardly with respect to said side wall 1110 provide a substantially annular space therebetween, :and substantially annular sealing structure carried by the peripheryof said floating roof and arranged in said-annular spaceand disposed :in slidingsealed engagement withsai'd side wall, whereby said float'ingroo'f is subject to rotation in a :gen- :erally horizontal plane with respect to said side wall; mechanism ,for controlling and limiting said rotation of said floating .roof comprising upper :anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardlyinto overhanging relation with respect to the outer peripheral portion "of said floating roof, lower 'anchor structure rigidly carried by said sidewall adjacent to the bottom'thereof and projecting generally radially inwardly into iunderhanging relation with respect to the outer peripheral :portion of said floating roof, said upper and lower sanchor structures being arranged substantially in vertical alignment with each other, :an outer peripheral portion of said floating roof havingan upstanding :passage therethrough, 'a strong flexible resilient vcablearranged said tank .and secured in taut condition between said upper and lower anchor structures and :extending through said upstanding passage, said 'floatingroof having a normal rotarycentered position with respect to said side wall wherein said upstanding passage is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, and a cable guidingdevice carried'by said floating roof adjacent tosaid upstanding passage and-engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough and through said upstanding 'passage incident to vertical movement in-either :direction of said floating roof with respect to said side-wall, said cable guiding device also being operative to accommodate radial movement in either direction of said floating roof =with1respect to the intermediate section of said cable-without corresponding deflection thereof from its substantially vertical position and to accommodate circumferential movement in either direction of'said floating roof "with respect to the intermediate section of said cable with corresponding-deflection thereof from :its substantially vertical position, whereby said thus deflected cable exerts a force through said cable guiding device upon "said'floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

2. -In a tank for storing liquids, such as petroleum products, including .an upstanding substantially cylindrical side Wall, a substantially disk-shaped piston-like floating roof arranged in said tank-in floating relation'with thestoredliquid and movable in the vertical direction with 'respect to said side wall in accordance with the head of the stored liquid, said floating roof beingpositioned radially inwardly with respect to said side wall to -provide asub stantially annular space therebetween, and substantially annular sealing structure-carried by theperip'hery'of said fioating roof and arranged in said annular space and :disposed in slidingsealed engagement with said side wall,

1 1 whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into over hanging relation with respect to the outer peripheral portion of said floating roof, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to the outer peripheral portion of said floating roof, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, an outer peripheral portion of said floatingroof having an upstanding passage therethrough, a strong flexible resilient cable arranged in said tank and secured in taut condition between said upper and lower anchor structures and extending through said upstanding passage, said floating roof having a normal rotary centered position with respect to said side wall wherein said upstanding passage is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, a cable guiding device carried by said floating roof adjacent to said upstanding passage and engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough and through said upstanding passage incident to vertical movement in either direction of said floating roof with respect to said side wall, and a sealing device carried by said floating roof and cooperating with said upstanding passage and the intermediate section of said cable in order to prevent any substantial escape of vapors from the stored liquid through said upstanding passage while accommodating ready feeding of said cable therethrough, undesirable rotation of said floating roof in either direction out of its normal rotary centered position causing said cable guiding device correspondingly to deflect the intermediate section of said cable from its substantially vertical position, whereby said thus deflected cable exerts a force through said cable guiding device upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

3. In a tank for storing liquids, such as petroleum products, including an upstanding substantially cylindrical side wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, said floating roof being positioned radially inwardly with respect to said side wall to provide a substantially annular space therebetween, and substantially annular sealing structure carried by the periphery of said floating roof and arranged in said annular space and disposed in sliding sealed engagement with said side wall, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to the outer peripheral portion of said floating roof, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to the outer peripheral portion of said floating roof, said upper and lower anchor structures being arranged substan tially in vertical alignment with each other, an outer peripheral portion of said floating roof having an upstanding passage therethrough, a strong flexible resilient cable arranged in said tank and secured in taut condition between said upper and lower anchor structures and extending through said upstanding passage, said floating roof having a normal rotary centered position with respect to said side wall wherein said upstanding passage is disposd in a position of vertical alignment with said upperand lower anchor structures and said cable occupies substantially a vertical position, a cable guiding device carried by said floatig roof adjacent to said upstanding passage and engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough and through said upstanding passage incident to vertical movement in either direction of said floating roof with respect to said side wall, and first and second sealing devices carried by said floating roof and respectively positioned below and above said cable guiding device, said first sealing device cooperating with said upstanding passage and the intermediate section of said cable in order to prevent any substantial escape of vapors from the stored liquid through said upstanding passage while accommodating ready feeding of said cable therethrough, said second sealing device cooperating with said cable guiding device and the intermediate section of said cable in order to prevent any substantial entry of rain and the other elements of weather into said cable guiding device while accommodating ready feeding of said cable therethrough, undesirable rotation of said floating roof in either direction out of its normal rotary centered position causing said cable guiding device correspondingly to deflect the intermediate section of said cable from its substantially vertical position, whereby said thus deflected cable exerts a force through said cable guiding device upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal centered position.

4. In a tank for storing liquids, such as petroleum products, including an upstanding substantially cylindrical side wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, said floating roof including a substantially annular outer pontoon provided with an outer rim and an inner rim and a top plate connecting the top portions of said outer and inner rims and a bottom plate connecting the bottom portions of said outer and inner rims, said outer rim being positioned radially inwardly with respect to said side wall to provide a substantially annular space therebetween, and substantially annular sealing structure carried by said outer rim and arranged in said annular space and disposed in sliding sealed engagement with said side wall, whereby said floating roof is subject to rotation in a generally horizontal plane with respect tosaid side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to said outer pontoon, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to said outer pontoon, said upper and lower anchor structures being arranged substantially in vertical alignment with each other,

an upstanding tube arranged in an outer peripheral portion of said outer pontoon and respectively sealed adjacent tothe top and bottom ends thereof to said top and bottom plates so as to define an upstanding passage through said tube and consequently through the outer peripheral portion of said outer pontoon, a strong flexible resilient cable arranged in said tank and secured in taut condition between said upper and lower anchor structures and extending through the upstanding passage in said tube, said floating roof having a normal rotary centered position with respect to said side wall wherein the upstanding passage in said tube is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, a pair of end plates carried by said top plate respectively adjacent to radially spaced-apart portions of the top end of said tube, a pair of elongated radially extending spindles carried by said end plates respectively adjacent to circumferentialiy spaced-apart portions of the top end of said tube, a pair of guide rollers respectively mounted upon said spindles for 'both rotational movements thereupon and radial sliding movements therealong and respectively-engaging the corresponding opposite sides of the intermediate section of said cable, one of said guide rollers carrying a pair of flanges respectively engaging the opposite sides of the other of said guide rollers so that said guide rollers are respectively slidable simultaneously along said spindles, said guide rollers accommodating ready feedingo'f said cable theret'hrough and through the upstanding opening'in said tube-incident to vertical movement in either'direction-of said floating roof with respect -to said side wall, said guide rollers accommodating radial movement in either direction of said floating roof with respect-to the intermediate section-ofsaiid cable by corresponding slidingo'f said guide rollers along said spindles and without corresponding deflection of the intermediate section of said cable from its substantially vertical position, side guide rollers accommodating circumferential movement in either direction of said floating roof with respect to the intermediate section of said cable withcorresponding deflection thereof "from its substantially vertical position, whereby said thus deflectedcable'exerts a force through the corresponding one-of said guide rollers upon said floating roof that is productive of a torque thereupon tending to restoresaid floating roof back into its normal rotary centered position, a first-sealing device carried by the topend'ofsaid tube and positioned below said guide rollers, said first sealing device cooperating with the upstanding passage in-said tube and the intermediate section of said cable in order to prevent 'anysubstantial escape of vapors from the stored liquid 'through'the =upstanding passage in said tube while accommodating ready feeding of said cable therethrough and ready radial movements'of said floating roof with respect to the intermediate section of'said cable,-a hood carried by said end plates and positioned above'said-guiderollersand having an opening therein through which said cable extends anda second sealing device-carried by said hood 'andcooperating'with the opening therein and the intermediatesection of said cable in order to prevent any substantial entry of rain and the other elements of weather into said hood while accommodating ready feeding of said cable therethrough and ready radial movements of said floating roof with respect tothe intermediate section ofsaid cable.

5. The combination set forth in claim 4, wherein each of 'said. first and second sealing devices essentially comprises a sheet-of flexible material having a radially extending slit'therein through whichthe intermediate section "of said cable extends.

6. The combinationset forth in claim 4, whereinthe dimension of said tubein the radial direction :is substantially greater than the dimension of said tube in the circumferential direction, thereby to accommodate radial movements in either direction of said floating roof with respect to the intermediate section of said cable without substantial engagement between said tube and said cable.

7. In a tank for storing liquids, suchas petroleumproducts, including an upstanding substantially cylindrical side Wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of tthestored liquid, said floating roof being positioned radially inwardly with respect to'said side wall to provide a substantially annular space therebetween, and substantially annular sealing structure of the resilient tubular-seal type carried 'by the periphery of said floating roof and arranged in said annular space and disposed in sliding sealed engagement with said side wall, whereby said sealing structure biases said floating roof into a normal radial centered position with respect to said side wall while accommodatingrotation of said floating roof in a generally'horizontal plane with respect to said side wan; mechanism forcontrolling and limiting said rotation of said floatingroof comprising upper anchor structure figidly carried by said side wall adjacent to the top thereof and projecting generzillyradiailly inwardly into overhanging relation with respect to the outer peripheral portion of -saidfloatingroofflower anchor structure rigidly carried by said side wall adjacent'to the bottom thereof and projecting generally radially inwardly into under'ha'ng'ing relation with respect to the outer peripheral portion of said floating roof, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, an 'outer peripheral portion of "said floating roof having an upstanding passage therethrough, a strong flexible resilient cable arranged in said tank andse'cured -in taut condition between said upper and lower anchor structures and extending through said upstanding passage, said floating roof having *a normal rotary centered position with respect to said side wall wherein said upstanding passage 'is'disposed in a positionof vertical alignment withsaid upperand lower anchor structures and said cable-occupies substantially a vertical position, and a cable guiding 'device carried by said floating roof adjacent to said upstandingpassage and engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough "and through said upstanding passage incident to vertical movement in either direction-of said-floatingroot with re- *spect to said'side 'wall, said cable guiding device alsobeing operative to accommodate radial movement in either direction (if said floating roof with'respect to the intermediate section of said cable without corresponding defle'ction "thereof from its substantially vertical position and to accommodate circumferential movement in either direction of said floating roof with respect to the intermediatesection-of-said cable with corresponding deflection thereof from its substantially verticalposition, whereby said thus deflected cable exerts a 'force through said cable guiding'device upon-saidfloating-roof that'is'productive (if-a torque thereupon tending to restore said-floating 'roofback intoits normal rotary centered position.

8. In a tank forstoring'liquids including 'an' upstanding substantially cylindrical side-wall, asubstantiallydiskshaped 'piston like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect'tosaid sidewall in accordance withthe 'headof *the stored liquid, and 'means "for positioning said floating roof radially inwardly With respect'to said=side wallto provide a substantially annular space therebetween, whereby said floating roof is subject torotation in a generally horizontal plane with respect to "said side 'wall; mechanism for controlling and limiting said rotation ofsaid floating roof comprising'upper-anchor structure rigidly carriedby said sidewall adjacent to the top thereof andprojecting generally radially inwardly into overhanging relation with respect to the outer peripheral portion of-said floating roof, lower anchorstructure-rigidly carried by said side wall adjacent'to the bottom thereof and projecting generally radially inwardly 'into underhanging relation with respect to 'the outer peripheral portion of said floating roof, said upper "and lower anchor structures being arranged substantially .in vertical alignment with each other, an outer peripheral portion of said floating roof having an upstanding passage therethrough,

a strong flexible resilient cable arranged in said tank and secured in tautcondition between said upper and lower anchor structures and extending through said upstanding passage, said floating roof having a normal rotary .cen-l tered position with respect to said side wall wherein said upstanding passage is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, and a cable guiding 'device carried by said floating roof adjacent to said upstanding passage and engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough and through said upstanding passage incident to vertical movement in either direction of said floating roof with respect to said side wall, said cable guiding device also being operative to accommodate radial movement in either direction of said floating roof with respect to the intermediate section of said cable without corresponding deflection thereof from its substantially vertical position and to accommodate circumferential movement in either direction of said floating roof with respect to the intermediate section of said cable with corresponding deflection thereof from its substantially vertical position, whereby said thus deflected cable exerts a force through said cable guiding device upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

9. The combination set forth in claim 8, wherein said cable is prestretched prior to its arrangement in taut condition between said upper and lower anchor structures and passing through said upstanding passage.

10. The combination set forth in claim 8, wherein said cable is formed essentially of stainless steel. 1

11. The combination set forth in claim 8, wherein said cable guiding device essentially comprises a pair of rollers respectively engaging the opposite sides of the intermediate section of said cable and mounted for rotation about a pair of substantially horizontally disposed and substantially radially directed axes.

12. The combination set forth in claim 8, wherein said cable guiding device essentially comprises an annular race surrounding the intermediate section of said cable and carrying a plurality of balls respectively engaging a corresponding plurality of circumferentially spaced-apart portions of said surrounded intermediate section of said cable.

13. The combination set forth in claim 8, wherein said cable guiding device essentially comprises a flanged sheave and a roller respectively engaging the opposite sides of the intermediate section of said cable, said roller also being positioned between the flanges of said sheave, and said sheave and said roller being mounted for rotation about two substantially horizontally disposed and substantially radially directed axes.

14. In a tank for storing liquids including an upstanding substantially cylindrical side wall, a substantially diskshaped piston-like floating roof arranged in said tanl; in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, and means for positioning said floating roof radially inwardly with respect to said side Wall to provide a substantially annular space therebetween, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to the outer peripheral portion of said floating roof, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into un-' derhanging relation with respect to the outer peripheral portion of said floating roof, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, an outer peripheral portion of said floating roof having an upstanding passage therethrough, a tension control device carried by said upper anchor structure, a strong flexible resilient cable arranged in said tank and secured in taut condition between said tension control device and said lower anchor structure and extending through said upstanding passage, said tension control device being selectively operable to preset the normal tension in said cable between said upper and lower anchor structures, said floating roof having a normal rotary centered position with respect to said side wall wherein said upstanding opening is disposed in a. position of vertical mediate section of said cable and accommodating ready.

feeding of said cable therethrough and through said upstanding passage incident to vertical movement in either direction of said floating roof with respect to said side wall, said cable guiding device also being operative to accommodate radial movement in either direction of said float ing roof with respect to the intermediate section of said cable without corresponding deflection thereof from its substantially vertical position and to accommodate circumferential movement in either direction of said floating roof with respect to the intermediate section of said cable with corresponding deflection thereof from its substantially vertical position, whereby said thus deflected cable exerts a force through said cable guiding device upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

15. In a tank for storing liquids including an upstanding substantially cylindrical side wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, and means for positioning said floating roof radially inwardly with respect to said side wall to provide a substantially annular space therebetween, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating 'roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to the outer peripheral portion of said floating roof, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to the outer peripheral portion of said floating roof, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, and outer peripheral portion of said floating roof having an upstanding passage therethrough, a resilient mounting and tension control device carried by said upper anchor structure, a strong flexible cable arranged in said tank and secured in taut condition between said resilient mounting and tension control device and said lower anchor structureand extending through said upstanding passage, said resilient mounting and tension control device introducing resiliency in the mounting of said cable between said upper and lower anchor structures and being selectively operable to preset the normal tension in said cable between said upper and lower anchor structures, said floating roof having a normal rotary centered position with respect to said side wall wherein said upstanding passage is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, and a cable guiding device carried by said floating roof adjacent to said upstanding passage and engaging the intermediate section or" said cable and accommodating ready feeding of said cable therethrough and through said upstanding passage incident to vertical movement in either direction of 17 a force through said cable guiding device upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

16. In a tank for storing liquids including an upstanding substantially cylindrical side wall having an open top, an annular outwardly directed curb carried by an annular outwardly directed curb carried by the top of said side wall, an annular outwardly directed wind girder carried by the upper portion of said side wall and positioned below said curb and extending radially outwardly well beyond said curb, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, and means for positioning said floating roof radially inwardly with respect to said side wall to provide a substantially annular space therebetween, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising an upper beam arranged at the top of said tank, the intermediate portion of said upper beam being rigidly mounted on the top of said curb, the outer end of said upper beam projecting generally radially outwardly into overhanging relation with respect to said wind girder and the inner end of said upper beam projecting generally radially inwardly into overhanging relation with respect to the outer peripheral portion of said floating roof, a tie connecting the outer end of said upper beam to said wind girder, a lower beam arranged in said tank adjacent to the bottom thereof, the outer end of said lower beam being rigidly secured to said side wall adjacent to the mottom thereof and the inner end of said lower beam projecting generally radially inwardly into underhanging relation with the outer peripheral portion of said floating roof, the inner ends of said upper and lower beams being arranged substantially in vertical alignment with each other, an outer peripheral portion of said floating roof having an upstanding passage therethrough, a strong flexible resilient cable arranged in said tank and secured in taut condition between the inner ends of said upper and lower beams and extending through said upstanding passage, said floating roof having a normal rotary centered position with respect to said side wall Wherein said upstanding passage is disposed in a position of vertical alignment with the inner ends of said upper and lower beams and said cable occupies substantially a vertical position, and a cable guiding device carried by said floating roof adjacent to said upstanding passage and engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough and through said upstanding passage incident to vertical movement in either direction of said floating roof with respect to said side wall, said cable guiding device also being operative to accommodate radial movement in either direction of said floating roof with respect to the intermediate section of said cable without corresponding deflection thereof from its substantially vertical position and to accommodate circumferential movement in either direction of said floating roof with respect to the intermediate section of said cable with corresponding deflection thereof from its substantially vertical position, whereby said thus deflected cable exerts a force through said cable guiding device upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

17. In a tank for storing liquids including an upstanding substantially cyl ndrical side wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, said floating roof including a substantially annular outer pontoon provided with an outer rim and an inner rim and a top plate connecting the top portions of said outer and inner rims and a bottom plate connecting the bottom portions of said outer and inner rims, and means for positioning said outer rim radially inwardly with respect to said side wall to provide a substantially annular space therebetween, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to said outer pontoon, lower anchor structure rigidly carried by said side Wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to said outer pontoon, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, an upstanding tube arranged in an outer peripheral portion of said outer pontoon and respectively sealed adjacent to the top and bottom ends thereof to said top and bottom plates so as to define an upstanding passage through said tube and consequently through the outer peripheral portion of said outer pontoon, a strong flexible resilient cable arranged in said tank and secured in taut condition between said upper and lower anchor structures and extending through the upstanding passage in said tube, said floating roof having a normal rotary centered position with respect to said side wall wherein the upstanding passage in said tube is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, and a cable guiding device carried by said top plate adjacent to said tube and engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough and through the upstanding passage in said tube incident to vertical movement in either direction of said floating roof with respect to said side wall, said cable guiding device also being operative to accommodate radial movement in either direction of said floating roof with repsect to the intermediate section of said cable without corresponding deflection thereof from its substantially vertical position and to accommodate circumferential movement in either direction of said floating roof with respect to the intermediate section of said cable with corresponding deflection thereof from its substantially vertical position, whereby said thus deflected cable exerts a force through said cable guiding device upon said floating roof that is productive to a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

18. In a tank for storing liquids including an upstanding substantially cylindrical side wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, and means for positioning said floating roof radially inwardly with respect to said side wall to provide a substantially annular space therebetween, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to 'the outer peripheral portion of said floating roof, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to the outer peripheral portion of said floating roof, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, an outer peripheral portion of said floating roof having an upstanding slotlike passage therethrough and orientated substantially in the radial direction, whereby said upstanding passage is relatively narrow in the circumferential direction and is relatively long in the radial direction, a strong flexible resilient cable arranged in said tank, and secured in taut condition between said upper and lower anchor structures and extending through said upstanding passage, said floating roof having a normal rotary centered position with respect to said side wall wherein said upstanding passage is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, and a cable guiding device carried by said floating roof adjacent to said upstanding passage and engaging the intermediate section of said cable and accommodating ready feeding of said cable therethrough and through said upstanding passage incident to vertical movement in either direction of said floating roof with respect to said side wall, said cable guiding device being operative to accommodate substantially unrestrained relative radial movements between said floating roof and the intermediate section of said cable and to accommodate no substan tial relative circumferential movements between said floating roof and the intermediate section of said cable, whereby undesirable rotation of said floating roof in either direction out of its normal rotary centered position causes said cable guiding device correspondingly to resolve such rotation into corresponding radial and circumferential motion components with the result that only the circumferential motion component of said floating root is applied to the intermediate section of said cable to deflect the same from its normal substantially vertical position, so that said thus deflected cable exerts a corresponding circumferentially applied force through said cable guiding device upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

19. In a tank for storing liquids including an upstanding substantially cylindrical side wall, a substantially disk-shaped piston-like floating roof arranged in said tank in floating relation wth the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, said floating roof including a substantially annular outer pontoon provided with an outer rim and an inner rim and a top plate connecting the top portions of said outer and inner rims and a bottom plate connecting the bottom portions of said outer and inner rims, and means for positioning said outer rim radially inwardly with respect to said side wall to provide a substantially annular space therebetween, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to said outer pontoon, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to said outer pontoon, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, an upstanding tube arranged in an outer peripheral portion of said outer pontoon and respectively sealed adjacent to the top and bottom ends thereof to said top and bottom plates so as to define an upstanding passage through said tube and consequently through the outer peripheral portion of said outer pontoon, a strong flexible resilient cable arranged in said tank and secured in taut condition between said upper and lower anchor structures and extending through the upstanding passage in said tube, said floating roof having a normal rotary centered position with respect to said side wall wherein the upstanding passage in said tube is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially a vertical position, a pair of elongated spindles carried by said top plate and extending in the radial direction and disposed on opposite sides of the upstanding passage in said tube, and a pair of elongated guide rollers respectively rotatably mounted upon said spindles and respectively engaging the corresponding opposite sides of the intermediate section of said cable, said guide rollers accommodating ready feeding of said cable therethrough and through the upstanding opening in said tube incident to vertical movement in either direction of said floating roof with respect to said side wall and accommodating radial movement in either direction of said floating roof with respect to the intermediate section of said cable without corresponding deflection thereof from its substantially vertical position and accommodating circumferential movement in either direction of said floating roof with respect to the intermediate section of said cable with corresponding deflection thereof from its substantially vertical position, whereby said thus deflected cable exerts a force through the corresponding one of said guide rollers upon said floating roof that is productive of a torque thereupon tending to restore said floating roof back into its normal rotary centered position.

20. In a tank for storing liquids including an upstanding substantially cylindrical side wall, a substantially diskshaped piston-like floating roof arranged in said tank in floating relation with the stored liquid and movable in the vertical direction with respect to said side wall in accordance with the head of the stored liquid, said floating roof including a substantially annular outer pontoon provided with an outer rim and an inner rim and a top plate connecting the top portions of said outer and inner rims and a bottom plate connecting the bottom portions of said outer and inner rims, and means for positioning said outer rim radially inwardly with respect to said side wall to provide a substantially annular space therebetween, whereby said floating roof is subject to rotation in a generally horizontal plane with respect to said side wall; mechanism for controlling and limiting said rotation of said floating roof comprising upper anchor structure rigidly carried by said side wall adjacent to the top thereof and projecting generally radially inwardly into overhanging relation with respect to said outer pontoon, lower anchor structure rigidly carried by said side wall adjacent to the bottom thereof and projecting generally radially inwardly into underhanging relation with respect to said outer pontoon, said upper and lower anchor structures being arranged substantially in vertical alignment with each other, an upstanding tube arranged in an outer peripheral portion of said outer pontoon and respectively sealed adjacent to the top and bottom ends thereof to said top and bottom plates so as to define an upstanding passage through said tube and consequently through the outer peripheral portion of said outer pontoon, a strong flexible resilient cable arranged in said tank and secured in taut condition between said upper and lower anchor structures and extending through the upstanding passage in said tube, said floating roof having a normal rotary centered position with respect to said side wall wherein the upstanding passage in said tube is disposed in a position of vertical alignment with said upper and lower anchor structures and said cable occupies substantially'a ventical position, a pair of elongated spindles carried by said top plate and extending in the radial direction and disposed on opposite sides of the upstanding passage in said tube, and a pair of guide rollers respectively mounted upon said spindles for both rotational movements thereupon and radial sliding movements therealong and respectively engaging the corresponding opposite sides of the intermediate section of said cable, one of said guide rollers carrying a pair of flanges respectively engaging the opposite sides of the other of said guide rollers so that said guide rollers are respectively slidable simultaneously along said spindles, said guide rollers accommodating ready feeding of said cable theretbrough and through the upstanding passage in said tube incident to vertical movement in 21 either direction of said floating roof with respect to said side wall, said guide rollers also accommodating radial movement in either direction of said floating roof with respect to the intermediate section of said cable by corresponding sliding of said guide rollers along said spindles and without corresponding deflection of the intermediate section of said cable from its substantially vertical position, side guide rollers further accommodating circumferential movement in either direction of said floating roof with respect to the intermediate section of said cable With corresponding deflection thereof from its substantially vertical position, whereby said thus deflected cable exerts a force through the corresponding one of said guide rollers upon said floating roof that is productive of a 15 2997200 torque thereupon tending to restore said floating roof back into its normal rotary centered position.

References (Zited in the file of this patent UNITED STATES PATENTS 1,121,057 Wilcox et al Dec. 15, 1914 1,674,104 Gallagher June 19, 1928 1,801,172 Patterson Apr. 14, 1931 1,816,124 Patterson July 28, 1931 2,280,768 Graver Apr. 21, 1942 2,350,483 Wiggins June 6, 1944 2,857,072 Bodley Oct. 21, 1958 2,867,346 Champagnat Jan. 6, 1959 Giannini et a1 Aug. 22, 1961 

1. IN A TANK FOR STORING LIQUIDS, SUCH AS PETROLEUM PRODUCTS, INCLUDING AN UPSTANDING SUBSTANTIALLY CYLINDRICAL SIDE WALL, A SUBSTANTIALLY DISK-SHAPED PISTON-LIKE FLOATING ROOF ARRANGED IN SAID TANK IN FLOATING RELATION WITH THE STORED LIQUID AND MOVABLE IN THE VERTICAL DIRECTION WITH RESPECT TO SAID SIDE WALL IN ACCORDANCE WITH THE HEAD OF THE STORED LIQUID, SAID FLOATING ROOF BEING POSITIONED RADIALLY INWARDLY WITH RESPECT TO SAID SIDE WALL TO PROVIDE A SUBSTANTIALLY ANNULAR SPACE THEREBETWEEN, AND SUBSTANTIALLY ANNULAR SEALING STRUCTURE CARRIED BY THE PERIPHERY OF SAID FLOATING ROOF AND ARRANGED IN SAID ANNULAR SPACE AND DISPOSED IN SLIDING SEALED ENGAGEMENT WITH SAID SIDE WALL, WHEREBY SAID FLOATING ROOF IS SUBJECT TO ROTATION IN A GENERALLY HORIZONTAL PLANE WITH RESPECT TO SAID SIDE WALL MECHANISM FOR CONTROLLING AND LIMITING SAID ROTATION OF SAID FLOATING ROOF COMPRISING UPPER ANCHOR STRUCTURE RIGIDLY CARRIED BY SAID SIDE WALL ADJACENT TO THE TOP THEREOF AND PROJECTING GENERALLY RADIALLY INWARDLY INTO OVERHANGING RELATION WITH RESPECT TO THE OUTER PERIPHERAL PORTION OF SAID FLOATING ROOF, LOWER ANCHOR STRUCTURE RIGIDLY CARRIED BY SAID SIDE WALL ADJACENT TO THE BOTTOM THEREOF AND PROJECTING GENERALLY RADIALLY INWARDLY INTO UNDERHANGING RELATION WITH RESPECT TO THE OUTER PERIPHERAL PORTION OF SAID FLOATING ROOF, SAID UPPER AND LOWER ANCHOR STRUCTURES BEING ARRANGED SUBSTANTIALLY IN VERTICAL ALIGNMENT WITH EACH OTHER, AN OUTER PERIPHERAL PORTION OF SAID FLOATING ROOF HAVING AN UPSTANDING PASSAGE THERETHROUGH, A STRONG FLEXIBLE RESILIENT CABLE ARRANGED IN SAID TANK AND SECURED IN TAUT CONDITION BETWEEN SAID UPPER AND LOWER ANCHOR STRUCTURES AND EXTENDING THROUGH SAID UPSTANDING PASSAGE, SAID FLOATING ROOF HAVING A NORMAL ROTARY CENTERED POSITION WITH RESPECT TO SAID SIDE WALL WHEREIN SAID UPSTANDING PASSAGE IS DISPOSED IN A POSITION OF VERTICAL ALIGNMENT WITH SAID UPPER AND LOWER ANCHOR STRUCTURES AND SAID CABLE OCCUPIES SUBSTANTIALLY A VERTICAL POSITION, AND A CABLE GUIDING DEVICE CARRIED BY SAID FLOATING ROOF ADJACENT TO SAID UPSTANDING PASSAGE AND ENGAGING THE INTERMEDIATE SECTION OF SAID CABLE AND ACCOMMODATING READY FEEDING OF SAID CABLE THERETHROUGH AND THROUGH SAID UPSTANDING PASSAGE INCIDENT TO VERTICAL MOVEMENT IN EITHER DIRECTION OF SAID FLOATING ROOF WITH RESPECT TO SAID SIDE WALL, SAID CABLE GUIDING DEVICE ALSO BEING OPERATIVE TO ACCOMMODATE RADIAL MOVEMENT IN EITHER DIRECTION OF SAID FLOATING ROOF WITH RESPECT TO THE INTERMEDIATE SECTION OF SAID CABLE WITHOUT CORRESPONDING DEFLECTION THEREOF FROM ITS SUBSTANTIALLY VERTICAL POSITION AND TO ACCOMMODATE CIRCUMFERENTIAL MOVEMENT IN EITHER DIRECTION OF SAID FLOATING ROOF WITH RESPECT TO THE INTERMEDIATE SECTION OF SAID CABLE WITH CORRESPONDING DEFLECTION THEREOF FROM ITS SUBSTANTIALLY VERTICAL POSITION, WHEREBY SAID THUS DEFLECTED CABLE EXERTS A FORCE THROUGH SAID CABLE GUIDING DEVICE UPON SAID FLOATING ROOF THAT IS PRODUCTIVE OF A TORQUE THEREUPON TENDING TO RESTORE SAID FLOATING ROOF BACK INTO ITS NORMAL ROTARY CENTERED POSITION. 